1864.] MwWiWiams^ Researches on Isomeric Alkaloids. 307 



an experiment to ascertain if the retardation was equal in tlie case of 

 /3-lutidine. 



V. (i-Lutidine. — A mixture, the exact strength of which is given in the 

 paper, containing a large excess of acid, was made. The whole instantly 

 hecame nearly solid, and in five minutes the beaker could be inverted with- 

 out any of the solid contents escaping. After twelve hours the weight of 

 crystals formed was 1*70 gramme. 



VI. Lutidine. — A precisely similar experiment was made with this base. 

 No crystals appeared for thirty minutes. In twelve hours only 0*68 

 gramme had formed. 



From the above experiments, it is evident that there is a vast difference 

 in the tendency of the two bases to form crystalline platinum-salts. 



Comparative Experiments upon the Decomposition hy boiling of the 



'Platinum-Salts of ^-Lutidine and Lutidine. 

 The author describes in his paper the nature of the apparatus, and the 

 precautions taken to ensure precision in the experiments. 



I. ^'Lutidine. — The salt begins to decompose the instant the solution 

 enters into ebullition, an insoluble powder beginning to deposit. After 

 forty minutes the operation had to be stopped, owing to the large quantity 

 of insoluble sulphur-yellow precipitate which had fallen and rendered the 

 boiling concussive. 



The salt formed in this manner was boiled with a fresh quantity of dis- 

 tilled water, and then analyzed. The numbers agreed with the formula 



/3n{^'^'}2HC1, 



which is that of the bihydrochlorate of platino-hitidine, if regarded as 

 analogous to the so-called bihydrochlorate of platinamine, 



II. Lutidine. — The solution of the salt required two hours and a half of 

 active boiling before even a trace of the insoluble precipitate began to form. 

 After several hours more boiling, the deposit was excessively small. The 

 author states that the difference in the behaviour of the two salts was so 

 great, that it would be easy at any time to distinguish the two platinum- 

 salts by this test alone. 



Platinum Compound of j^-Imtidine isomeric with the Bihydrochlorate of 

 Platino-fi-Lutidine. 

 The author states his opinion that Gerhard t's theory of the platinum 

 bases will require some modification to enable it to be applied to the ana- 

 logous bodies obtained from the tertiary monamines. The bihydrochlo- 

 rate of platinamine, the empirical formula of which is NIP, Pt CP, accord- 

 ing to Gerhardt is constituted thus : — 



n|^|2HC1; 



but the author concludes that this formula is unsuitable to nitryle bases, 



VOL. XIII. 2 A 



